1. Field of the Invention
The present invention relates to a processing tool which is attached detachably to the main spindle of a machine tool such as a machining center so as to execute processing such as chamfering, deburring, or lapping a work piece by rotating a cutter (including a deburring tool, a lapping tool, etc) by means of the main spindle.
2. Description of the Related Art
Conventionally, as a processing tool, which is attached detachably to the main spindle of a machine tool such as a machining center so as to execute processing such as deburring, a deburring unit as disclosed in Japanese Patent Application Laid-Open No. 8-57758 has been known. In this deburring unit, its main body unit can be mounted to the main spindle of a machine tool, an air motor is installed at the bottom of the main body unit in such a condition that it is tilted obliquely downward with a deburring tool attached to the front end of its drive shaft and then, the deburring tool being rotated by the air motor is pressed against the processing face of a work piece so as to deburr the work piece.
However, because the above-mentioned deburring unit drives the deburring tool by means of an air motor, there is a problem in that a supply source for supplying pressurized air to the air motor is required. Furthermore, the air motor is installed on the main body unit in such a way that it is tilted vertically and the tilting direction of the deburring tool mounted to the rotational shaft is therefore determined depending on the tilting angle of the air motor. Thus, the angle (direction) of the main body unit needs to be controlled so that the direction of the cutting edge of the deburring tool is always the appropriate one, thereby resulting in a complication of the required control mechanism and control program.
Further, because the air motor and the deburring tool attached to the front end of the rotational shaft are mounted obliquely in advance, sometimes the tool cannot be controlled smoothly by simply tilting the tool relative to the processing surface of a work piece which has various angles. Consequently, there is a problem in that a process such as deburring the edge portion of a work piece cannot be carried out favorably and smoothly depending on the angle of the processing face.